I am currently working on a Phillips tv (32PFL3403D-27) that had stopped working a while back. First it started shutting off from time to time or even turning itself on from time to time. Eventually, it wouldn't even turn on other than the power light being on. I pulled the power board (picture below) out and with it powered on I am getting no voltage (24 V or 12 V) at the outputs for the scalar or panel. I am getting the 5 V output, but that is it.
Tracing the schematic (attached below), I saw that the voltage for those pins comes off of the secondary of the larger transformer (T901). I am getting no voltage at the secondary, but I do have power on the primary side of that transformer. The top 3 pins of the transformer have 360 VAC between them and the ground side of the primary (bottom pin). I did find a bad capacitor (C932), but that capacitor was after the secondary of the transformer which is currently receiving no voltage, so I know that is not the issue, but maybe played a role when the tv first started acting up.
I am leaning towards the transformer being bad, but I wanted to get opinions on this. I'm really not sure what I'm supposed to have on the primary side and since it seems finding parts for this board isn't that easy, I want to make sure I'm not overlooking anything. Any thoughts?
Tracing the schematic (attached below), I saw that the voltage for those pins comes off of the secondary of the larger transformer (T901). I am getting no voltage at the secondary, but I do have power on the primary side of that transformer. The top 3 pins of the transformer have 360 VAC between them and the ground side of the primary (bottom pin). I did find a bad capacitor (C932), but that capacitor was after the secondary of the transformer which is currently receiving no voltage, so I know that is not the issue, but maybe played a role when the tv first started acting up.
I am leaning towards the transformer being bad, but I wanted to get opinions on this. I'm really not sure what I'm supposed to have on the primary side and since it seems finding parts for this board isn't that easy, I want to make sure I'm not overlooking anything. Any thoughts?
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